There are pneumatic tires that have a plurality of main grooves in the tread portion extending in the tire circumferential direction, where a plurality of rows of land portions with rib trends are demarcated by the main grooves. With this type of pneumatic tire, the width of each land portion is generally set to be wide if there is a focus on handling stability. However, if the land portions are set to be wide, there is a tendency that the ground contact pressure will be relatively high at the edge portions of each land portion, and when driving under these conditions, the footprint length is reduced in the circumferential direction of the tire in a center portion of each land portion, and this is a factor that reduces handling stability.
In this regard, a proposal has been made to appropriately set the ground contact condition of each land portion, by projecting the road contact surface of the land portions demarcated by the main grooves in the tread portion, toward the outer side in the radial direction of the tire (for example, refer to Japanese Unexamined Patent Application Publication Nos. 2004-122904A, 2002-29216A or 2005-263180A).
However, even if the road contact surface of each land portion of the tread portion is projected to the outer side in the radial direction of the tire, the current condition is that improving the ground contact condition proximal to a shoulder main groove located on the outermost side in the tire width direction is difficult, and the effect of improving the handling stability cannot necessarily be sufficiently achieved.
Furthermore, the aforementioned pneumatic tires are required to simultaneously demonstrate excellent uneven wear resistance performance, in addition to excellent handling stability. In particular, there is a tendency for the shoulder land portion to undergo preferential wear as compared to the center land portion, and there is strong demand to prevent this type of uneven wear. However, a structure where the road contact surface of each land portion of the tread portion is projected to the outer side in the tire radial direction will not exhibit an effect of improving the uneven wear resistance.